A new C/C++ frontend is being developed -
clang. It's aimed for the LLVM compiler
infrastructure. The interesting part is the
motivation for it (you can read about it in the slides introducing
it) - the main goal
is to get a good intermediate representation (AST) which can be easily
consumed by other tools (static code analysis, etc.) Moreover, they want
to have excellent diagnostics support (though this smells like fixing
the problems with C and C++ from the wrong side, in my opinion the
syntax is long due for an overhaul). Looks very interesting, and as
Apple is behind this, there is hope that this
one will eventually become usable.